Bulkhead seals have long been used in the construction of ships. Such seals are normally installed between each bulkhead of a ship and the propeller shaft. Normally these seals have no function. They are held in a non-operative condition during which the main propeller shaft seal holds out the sea water. However, should the hull of the ship be ruptured, it is desirable to actuate the seal in adjacent bulkheads to preclude flooding of the separate compartments defined by the bulkheads. The non-flooded compartments will maintain the bouyancy of the ship.
U.S. Pat. No. 3,948,531 (Mitrani) illustrates one type of bulkhead seal. Seals made pursuant to this patent have been sold and are effective. However, our invention seeks to improve upon this seal in terms of lower cost, simplicity and ease of actuation.